[PATCH v2 47/49] PCI, x86: Add pci=assign_pref_bars to re-allocate pref bars

Yinghai Lu
2015-07-14T22:53:22Z

So could reallocate pref mmio64 above 4G later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
arch/x86/include/asm/pci_x86.h | 1 +
arch/x86/pci/common.c | 3 +++
arch/x86/pci/i386.c | 56 ++++++++++++++++++++++++++----------------
3 files changed, 39 insertions(+), 21 deletions(-)

diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index ddac225..7b634b8 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -34,6 +34,7 @@ do { \
#define PCI_NOASSIGN_ROMS 0x80000
#define PCI_ROOT_NO_CRS 0x100000
#define PCI_NOASSIGN_BARS 0x200000
+#define PCI_ASSIGN_PREF_BARS 0x400000

extern unsigned int pci_probe;
extern unsigned long pirq_table_addr;
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index e8df922..dcc7c48 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -606,6 +606,9 @@ char *__init pcibios_setup(char *str)
} else if (!strcmp(str, "assign-busses")) {
pci_probe |= PCI_ASSIGN_ALL_BUSSES;
return NULL;
+ } else if (!strcmp(str, "assign_pref_bars")) {
+ pci_probe |= PCI_ASSIGN_PREF_BARS;
+ return NULL;
} else if (!strcmp(str, "use_crs")) {
pci_probe |= PCI_USE__CRS;
return NULL;
diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 3f17726..0b74efe 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -208,16 +208,25 @@ static void pcibios_allocate_bridge_resources(struct pci_dev *dev)
continue;
if (r->parent) /* Already allocated */
continue;
- if (!r->start || pci_claim_bridge_resource(dev, idx) < 0) {
- /*
- * Something is wrong with the region.
- * Invalidate the resource to prevent
- * child resource allocations in this
- * range.
- */
- r->start = r->end = 0;
- r->flags = 0;
- }
+
+ if ((r->flags & IORESOURCE_PREFETCH) &&
+ (pci_probe & PCI_ASSIGN_PREF_BARS))
+ goto clear;
+
+ if (!r->start)
+ goto clear;
+
+ if (pci_claim_bridge_resource(dev, idx) == 0)
+ continue;
+
+clear:
+ /*
+ * Something is wrong with the region.
+ * Invalidate the resource to prevent
+ * child resource allocations in this range.
+ */
+ r->start = r->end = 0;
+ r->flags = 0;
}
}

@@ -263,21 +272,26 @@ static void pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
else
disabled = !(command & PCI_COMMAND_MEMORY);
if (pass == disabled) {
+ if ((r->flags & IORESOURCE_PREFETCH) &&
+ (pci_probe & PCI_ASSIGN_PREF_BARS))
+ goto clear;
+
dev_dbg(&dev->dev,
"BAR %d: reserving %pr (d=%d, p=%d)\n",
idx, r, disabled, pass);
- if (pci_claim_resource(dev, idx) < 0) {
- if (r->flags & IORESOURCE_PCI_FIXED) {
- dev_info(&dev->dev, "BAR %d %pR is immovable\n",
- idx, r);
- } else {
- /* We'll assign a new address later */
- pcibios_save_fw_addr(dev,
- idx, r->start);
- r->end -= r->start;
- r->start = 0;
- }
+ if (pci_claim_resource(dev, idx) == 0)
+ continue;
+ if (r->flags & IORESOURCE_PCI_FIXED) {
+ dev_info(&dev->dev, "BAR %d %pR is immovable\n",
+ idx, r);
+ continue;
}
+
+clear:
+ /* We'll assign a new address later */
+ pcibios_save_fw_addr(dev, idx, r->start);
+ r->end -= r->start;
+ r->start = 0;
}
}
if (!pass) {
--
1.8.4.5